private unsafe int Find(UF *uf, int a)
{
Debug.Assert(IsInRange(a));
if (uf[a].Parent != a)
{
uf[a].Parent = Find(uf[a].Parent);
}
return(uf[a].Parent);
}
private unsafe int Find(UF *uf, int a)
{
Debug.Assert(IsInRange(a));
if (s_stack == null)
{
s_stack = new Stack <int>();
}
while (uf[a].Parent != a)
{
s_stack.Push(a);
a = uf[a].Parent;
}
while (s_stack.Count > 0)
{
int k = s_stack.Pop();
uf[k].Parent = a;
}
return(a);
}
// This version is about 10% faster than recursive
private unsafe int Find(UF *uf, int a)
{
Debug.Assert(IsInRange(a));
step *s = null;
while (uf[a].Parent != a)
{
step *c = stackalloc step[1];
c->Element = a;
c->Prev = s;
s = c;
a = uf[a].Parent;
}
while (s != null)
{
uf[s->Element].Parent = a;
s = s->Prev;
}
return(a);
}
